GPI TM Series Water Meter. Part Number Alternate P/N Flow Rate / Size Fitting Display / Output Price; TM050. The Ashcroft 1279 Duragauge pressure gauge is the finest production gauge on the market for industrial use where precise indications are required.. Ashcroft Type 200 Series diaphragm seals are available with process connection ranging from 1/4 to 8 inches in a wide variety of process connection materials..